/*
 * Created on 1 Nov 2006
 * Created by Paul Gardner
 * Copyright (C) Azureus Software, Inc, All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 */

package com.aelitis.azureus.core.networkmanager.admin.impl;

import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.nio.channels.SocketChannel;
import java.util.ArrayList;
import java.util.List;

import org.gudy.azureus2.core3.util.AESemaphore;

import com.aelitis.azureus.core.networkmanager.ProtocolEndpoint;
import com.aelitis.azureus.core.networkmanager.ProtocolEndpointFactory;
import com.aelitis.azureus.core.networkmanager.admin.NetworkAdminException;
import com.aelitis.azureus.core.networkmanager.admin.NetworkAdminSocksProxy;
import com.aelitis.azureus.core.networkmanager.impl.tcp.ProtocolEndpointTCP;
import com.aelitis.azureus.core.networkmanager.impl.tcp.ProxyLoginHandler;
import com.aelitis.azureus.core.networkmanager.impl.tcp.TCPConnectionManager;
import com.aelitis.azureus.core.networkmanager.impl.tcp.TCPNetworkManager;
import com.aelitis.azureus.core.networkmanager.impl.tcp.TCPTransportHelperFilterFactory;
import com.aelitis.azureus.core.networkmanager.impl.tcp.TCPTransportImpl;
import com.aelitis.azureus.core.versioncheck.VersionCheckClient;

public class NetworkAdminSocksProxyImpl implements NetworkAdminSocksProxy {
    private final String TARGET_HOST = VersionCheckClient.HTTP_SERVER_ADDRESS_V4;
    private final int TARGET_PORT = VersionCheckClient.HTTP_SERVER_PORT;

    private String host;
    private String port;

    private String user;
    private String password;

    protected NetworkAdminSocksProxyImpl(String _host, String _port, String _user, String _password) {
        host = _host;
        port = _port;
        user = _user;
        password = _password;
    }

    protected boolean isConfigured() {
        return (host.length() > 0);
    }

    public String getName() {
        return (host + ":" + port);
    }

    public String getHost() {
        return (host);
    }

    public String getPort() {
        return (port);
    }

    public String getUser() {
        return (user);
    }

    public String[] getVersionsSupported()

    throws NetworkAdminException {
        NetworkAdminException failure = null;

        List versions = new ArrayList();

        try {
            testVersion("V4");

            versions.add("4");

        } catch (NetworkAdminException e) {

            failure = e;
        }

        try {
            testVersion("V4a");

            versions.add("4a");

        } catch (NetworkAdminException e) {

            failure = e;
        }

        try {
            testVersion("V5");

            versions.add("5");

        } catch (NetworkAdminException e) {

            failure = e;
        }

        if (versions.size() > 0) {

            return ((String[]) versions.toArray(new String[versions.size()]));

        }

        throw (failure);
    }

    public String getString() {
        String res = getName();

        if (user.length() > 0) {

            res += " [auth=" + user + "]";
        }

        res += ", versions=";

        try {
            String[] versions = getVersionsSupported();

            for (int j = 0; j < versions.length; j++) {

                res += (j == 0 ? "" : ",") + versions[j];
            }

        } catch (NetworkAdminException e) {

            res += "unknown (" + e.getLocalizedMessage() + ")";
        }

        return (res);
    }

    protected void testVersion(final String version)

    throws NetworkAdminException {
        final int RES_CONNECT_FAILED = 0;
        final int RES_SOCKS_FAILED = 1;
        final int RES_OK = 3;

        final AESemaphore sem = new AESemaphore("NetworkAdminSocksProxy:test");

        final int[] result = { RES_CONNECT_FAILED };

        final NetworkAdminException[] error = { null };

        try {
            InetSocketAddress socks_address = new InetSocketAddress(InetAddress.getByName(host), Integer.parseInt(port));

            final InetSocketAddress target_address = new InetSocketAddress(TARGET_HOST, TARGET_PORT);

            TCPConnectionManager.ConnectListener connect_listener = new TCPConnectionManager.ConnectListener() {
                public int connectAttemptStarted(int default_connect_timeout) {
                    return (default_connect_timeout);
                }

                public void connectSuccess(SocketChannel channel) {
                    final TCPTransportImpl transport =
                            new TCPTransportImpl((ProtocolEndpointTCP) ProtocolEndpointFactory.createEndpoint(ProtocolEndpoint.PROTOCOL_TCP,
                                    target_address), false, false, null);

                    transport.setFilter(TCPTransportHelperFilterFactory.createTransparentFilter(channel));

                    new ProxyLoginHandler(transport, target_address, new ProxyLoginHandler.ProxyListener() {
                        public void connectSuccess() {
                            transport.close("Done");

                            result[0] = RES_OK;

                            sem.release();
                        }

                        public void connectFailure(Throwable failure_msg) {
                            transport.close("Proxy login failed");

                            result[0] = RES_SOCKS_FAILED;
                            error[0] = new NetworkAdminException("Proxy connect failed", failure_msg);

                            sem.release();
                        }
                    }, version, user, password);
                }

                public void connectFailure(Throwable failure_msg) {
                    result[0] = RES_CONNECT_FAILED;
                    error[0] = new NetworkAdminException("Connect failed", failure_msg);

                    sem.release();
                }
            };

            TCPNetworkManager.getSingleton().getConnectDisconnectManager().requestNewConnection(socks_address, connect_listener,
                    ProtocolEndpoint.CONNECT_PRIORITY_MEDIUM);

        } catch (Throwable e) {

            result[0] = RES_CONNECT_FAILED;
            error[0] = new NetworkAdminException("Connect failed", e);

            sem.release();
        }

        if (!sem.reserve(10000)) {

            result[0] = RES_CONNECT_FAILED;
            error[0] = new NetworkAdminException("Connect timeout");
        }

        if (result[0] != RES_OK) {

            throw (error[0]);
        }
    }
}
